The present invention relates to a metal roof having interlocking standing seams which can disengage in heavy winds, wherein a transverse bar is provided across the standing seams, the transverse bar being clamped to the standing seams, and the transverse bar having a series of downward extending brackets each of which has a flexible foot to press down on the flat panels of the roof, thereby providing a structural brace to hold the panels down in a heavy wind.
Metal roofs formed by interconnected metal panels can be susceptible to uplift and tearing due to lifting forces caused thereon by blowing winds. Such wind blown metal panels can be hazardous to nearby people and property. For example, during particularly windy conditions, metal panels can detach or tear from the metal roof and injure passers-by. As such, and with the increased use of metal panels in building construction, there has been an increased need to address ways in which to simply and conveniently control the uplift of such metal roofs.
In addition, in various climates it may be desirable to position a snow retention device on a metal roof to control/inhibit/impede the movement of snow and/or ice down the pitch of the roof.
Sliding snow and/or ice from roofs can be hazardous to people, the surrounding landscape, property, and building components. For example, snow or ice sliding from a roof above an entryway may injury passers-by. Similarly, falling snow or ice can be damage to landscape features, such as shrubs, and property or building components, including automobiles or lower roofing portions. In addition, sliding snow or ice can shear off antennas, gutters or other components attached to a building roof or wall, thereby potentially causing a leak. The problem of sliding snow or ice is particularly experienced in connection with metal roofs, including raised seam roofs (e.g. standing seam), where there is relatively little friction between the roof and the snow or ice. As used herein, the term xe2x80x9craised seam roofsxe2x80x9d includes roofs formed by a series of panels interconnected to define longitudinal, raised portions. It may, therefore, be desirable to provide a guard suitable for controlling movement of snow and/or ice across/along selected areas of such metal roofs.
The forerunner of the present invention is the snow retention device taught in U.S. Pat. No. 5,271,194 (1993) to Drew.
The device used in the ""194 method of preventing sheets of snow from falling from sheet metal roofs comprises a plurality of attachment mechanisms, each capable of supporting a bar which extends perpendicular to the roof seams. The attachment mechanisms are generally U-shaped, with two prongs and an apex. Thus, the attachment mechanisms may fit around a variety of different widths of roof seams. Furthermore, the attachment mechanisms will conveniently fit around roof seams which are broader at one point than another, such as a seam that is broader at the top than at the point of connection to the roof.
To facilitate securing the attachment mechanisms to roof seams, a hole is provided in one or both prongs of each attachment mechanism, for received an attachment screw. The attachment screw has a blunt tip which will not penetrate the roof seam as the attachment screw is tightened to hold the attachment mechanism in place next to the roof seam.
The ""194 method of preventing large sheets of snow from falling off roofs involves attaching a plurality of attachment mechanisms to roof seams. It is not essential that every roof seam be fitted with an attachment mechanism, as long as sufficient attachment mechanisms are connected to roof seams to provide support for the bar to be held in place by the attachment mechanisms. The attachment mechanisms should be aligned so that the bar may be placed adjacent to the apex of each attachment mechanism. The next step in the ""194 method is to connect the bar to the attachment mechanisms. This may be accomplished by screwing, welding, or otherwise connecting the bar directly to the apex of each attachment mechanism, holding the bar essentially perpendicular to the roof seams and adjacent to said apexes while the connections are being made.
A more convenient method of connecting the attachment mechanisms to the bar may be utilized. In this method, each attachment mechanism is provided with a bar receiving channel, connected to the apex of the attachment mechanism prior to connecting the attachment mechanisms to the roof seams. This channel is designed to snugly receive the bar, so that the bar may be placed into plurality of channels to hold the bar in its desired position with respect to the roof. Thus, once the attachment mechanisms are attached to the roof seams, the bar may be placed into the channels which hold the bar in place.
To further secure the bar in its desired location, a securing screw may be inserted through one or more of the channels into the bar. A hole may be provided in each channel to facilitate placement of the securing screw. The securing screw may be inserted through the channel opposite the connection of the channel to the apex of the U-shaped attachment mechanism. Alternatively, if more convenient, the securing screw may be inserted through the apex of the U-shaped attachment mechanism, through the channel at its point of connection to that apex, and into the bar.
Use of attachment mechanisms with bar receiving channels facilitates installation of this device for preventing sheets of snow from falling in a number of ways. Even when roof seams are spaced with differing distances between adjacent seams, use of separate attachment mechanisms enables the mechanisms to be quickly installed without modification. Then, the bar may be conveniently placed in the channels of each attachment mechanism, again with no modification required to adjust for differing distances between adjacent roof seams. Similarly, the bar may be easily placed into the channels without regard for the size or shape of each individual seam, differences in which are accommodated by placing each U-shaped attachment mechanism over the seam with a prong on either side of the seam.
Another advantage of the ""194 invention is that the bar may be easily removed from the attachment mechanisms. If a significant build-up of snow occurs, it may be desirable to push that snow off the roof at a time when the area beneath the roof can be cleared of anyone or anything that might be hurt by the snow. The bar can be removed at such a time, the snow pushed off the roof, and the bar easily reinserted into the channels of the attachment mechanism.
The ""194 system has also been improved for snow retention purposes to include a downward depending bracket located between the standing seams and fastened to the transverse bar. In the marketplace this bracket has been called the optional ice stopper. The bottom edge of the optional ice stopper consists of a narrow elongate edge of the metal body of the ice stopper. This narrow elongate edge if used as an anti-lift mechanism for the roof panels would puncture or otherwise damage the thin gauge metal roof panels.
Therefore, what is needed to upgrade the basic structure of the ""194 patent with the optional ice stopper is a foot for the downward depending bracket. The foot needs to spread the downward force of the bracket during high winds across a large enough surface area of the roof panel to prevent damage to the roof panel. The present invention teaches several embodiments of an adequate foot design.
The preferred embodiment uses a neoprene pedastal as the foot, wherein the pedastal has a groove to fit under the bracket""s lower edge. The resultant device provides structural integrity to the center of the roof panel for prevention of uplift during high winds. A plurality of transverse bars are used across the entire roof for this wind uplift prevention system. In some climates such as Boulder, Colorado the invention serves both as a wind uplift prevention system and a snow retention system.
The primary aspect of the present invention is to provide a plurality of transverse bars across the tops of standing seams of a metal roof, wherein each bar supports a downward depending structural brace against a portion of a roof panel, thereby preventing wind uplift of the panel while not causing harm to the panel.
Another aspect of the present invention is to provide each brace with a foot designed to push down on the flat roof panel without damaging the flat roof panel.
Other aspects of this invention will appear from the following description and appended claims, reference being made to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.
The present design incorporates a clamp that fits 95% of the architectural and structural standing seams on the market. The system consists of a 12 gauge stainless steel clamp which holds a 16 gauge 1xe2x80x3xc3x971xe2x80x3 stainless steel bar that is fastened to the clamp. The downward braces that hang from the bar in the center of the panel prevent wind uplift without injury to the panel. They can also be used to prevent ice from sliding under the bar on high structural seams or over entryways where more protection is needed.
The system is not only a clamp but is also a bar. By incorporating a 16 gauge stainless bar which is strong enough not to deflect between the seams, and using a clamp at every seam, the system creates a very rigid grid that if properly engineered will hold down a metal roof even in a hurricane.
All the embodiments provide a clamp and a bar assembly(s) for controlling the amount of upward deflection of the flat of the panel of a standing seam metal roof system, thereby preventing the interlocking seams of the roof system from deforming and disengaging.
The preferred embodiment consists of a plurality of clamping devises that attach to the vertical seams of a standing seam metal roof and fastens to those seams with a blunt tip screw(s) that will not penetrate the standing seam. These clamping devises incorporate a U-shaped yoke to receive a structural bar of size designed to span between the specific seam spacing and running perpendicular to the standing seams. The bar is snuggly fit into the yoke of the clamp assembly and is further attached to the clamp through one of its sides with two or more screws.
The bar securely fastens to the clamping device which are themselves attached to the vertical seams of the roof. The bar can now act as a structural support for the wind uplift brace that attaches to the bar/clamp assembly. This brace which can vary in its length is shaped in a xe2x80x9cU xe2x80x9d fashion so as to drop over the bar in a snug fit; it""s vertical leg extending down to the flat of the standing seam panel. The brace is then fastened to the bar with two screws. This can be of different shapes and designs to facilitate the various dimensions, depths and configurations of the many manufacturers of metal standing seam roofing. The brace will be positioned approximately in the middle of the distance between the individual standing seams. Although some applications may use multiple braces across one panel span. The base of the foot brace may contain a receiving slot for a rubber, neoprene, nylon or plastic foot to prevent it from marring the surface of the metal roof. The base of the foot may or may not touch the surface of the roof panel, but will be no more than xc2xdxe2x80x3 from the flat portion of the panel. The purpose of the foot is to prevent the flat of the panel from being forced up by the positive and negative pressures of high velocity winds blowing over the surface of the roof panels. These pressures will be transferred through the foot to the brace and in turn to the bar and finally into the clamp which are securely fastened to the seams. By reducing the deflection of the flat of the panel you will prevent the spreading of the standing seam interlock and thereby prevent its eventual deformation and disengagement.
The frequency or occurrence of the rows of bar assemblies up the roof will be determined by the roof type, style, and roof support spacing. In most cases a plurality of bar assemblies will occur over each support or in the mid-span of the roof panels between the roof supports.